SWITCH-TO-IBM YES
When SWITCH-TO-IBM YES is specified in hlq.CDBAPARM(UTIL), the IBM utility is invoked to process unsupported features or objects. When IBM is invoked, the CA ddnames in the JCL are mapped to the following IBM ddnames.
Has there been any change in this between R18 and R19?
Little change between R18 and R19 with this feature.
just a few changes for V12 support and that's it.